Over 1 million men and women in the United States alone are currently infected with HIV, and around 15% of them remain undiagnosed. In 2011, the total population of HIV infection was already 34 million. HIV is also responsible for 1.7 million deaths around the globe.
HIV is a pandemic, yet despite having been around for many years, it's still not clear how, when, and where it happened. Today, however, we may already get the answers.
In an article published by the University of Oxford on Friday, October 3, entitled "HIV Pandemic's Origins Located," a team of researchers from University of Leuven and Oxford University was able to determine with a very high level of uncertainty where the deadly virus strains came from and how it spread globally and became a pandemic.
Using certain techniques such as phylogeographic and analytic methods like spatiotemporal origins, tracing the origins of HIV-1 group M, they were able to pinpoint that the virus may have likely begun in Kinshasa, Democratic Republic of the Congo's capital. They had also placed the timeline around 1920s, which made the virus quite older than we believed it to be.
But what caused the worldwide infection? First, one should note that the virus, which is believed to have come from primates, has actually been transmitted more than 10 times to humans, but only one of these instances led to the pandemic.
But as to its spread, it can be attributed to a lot of factors. One, around this time, Kinshasa already had an excellent transport system via the railway. Back then, the country, whose size is comparable to that of Western Europe, was one of the most connected cities in Central Africa. By 1940s alone more than a million people had been using the railway each year. This efficient transport link led to the second wave of HIV transmission. They also cited the growth of its population and the differences of genetic structures of HIV-1 Group M that was found in the country with the other virus strains. However, they also didn't discount the other changes during that time such as in public health and sex trade.